/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.hudi.util;

import org.apache.spark.sql.types.ArrayType;
import org.apache.spark.sql.types.DataType;
import org.apache.spark.sql.types.Decimal;
import org.apache.spark.sql.types.DecimalType;
import org.apache.spark.sql.types.MapType;
import org.apache.spark.sql.types.StructField;
import org.apache.spark.sql.types.StructType;

import java.util.Arrays;

public class DataTypeUtils {

  /**
   * Checks whether provided {@link DataType} contains {@link DecimalType} whose scale is less than
   * {@link Decimal#MAX_LONG_DIGITS()}
   */
  public static boolean hasSmallPrecisionDecimalType(DataType sparkType) {
    if (sparkType instanceof StructType) {
      StructField[] fields = ((StructType) sparkType).fields();
      return Arrays.stream(fields).anyMatch(f -> hasSmallPrecisionDecimalType(f.dataType()));
    } else if (sparkType instanceof MapType) {
      MapType map = (MapType) sparkType;
      return hasSmallPrecisionDecimalType(map.keyType()) || hasSmallPrecisionDecimalType(map.valueType());
    } else if (sparkType instanceof ArrayType) {
      return hasSmallPrecisionDecimalType(((ArrayType) sparkType).elementType());
    } else if (sparkType instanceof DecimalType) {
      DecimalType decimalType = (DecimalType) sparkType;
      return decimalType.precision() < Decimal.MAX_LONG_DIGITS();
    }

    return false;
  }
}
